@article{Floyd_1962,
    doi = {10.1145/368959.368993},
    url = {https://doi.org/10.1145%2F368959.368993},
    year = {1962},
    month = {oct},
    publisher = {Association for Computing Machinery ({ACM})},
    volume = {5},
    number = {10},
    pages = {526},
    author = {Robert W. Floyd},
    title = {On ambiguity in phrase structure languages},
    journal = {Communications of the {ACM}}
}

@article{Floyd_1962, doi = {10.1145/368959.368993}, url = {https://doi.org/10.1145%2F368959.368993}, year = {1962}, month = {oct}, publisher = {Association for Computing Machinery ({ACM})}, volume = {5}, number = {10}, pages = {526}, author = {Robert W. Floyd}, title = {On ambiguity in phrase structure languages}, journal = {Communications of the {ACM}} }